The UTF-16 character represented by this glyph.
The BMFont character code.
UTF-16 character index across drawn lines, excluding line breaks.
Elapsed update time in milliseconds while the effect is enabled.
Unmodified glyph destination coordinates, after alignment and scaling.
The natural phase source for a travelling effect: deriving it from GlyphEffectContext.index instead advances the wave as far across a narrow glyph as a wide one, so its wavelength changes with whatever the line spells.
Reused per-glyph context. Read its values during the callback only.